Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl-2.6

[safe/jmp/linux-2.6] / arch / ia64 / kernel / crash.c

diff --git a/arch/ia64/kernel/crash.c b/arch/ia64/kernel/crash.c
index 3f3a579..b942f40 100644 (file)
--- a/arch/ia64/kernel/crash.c
+++ b/arch/ia64/kernel/crash.c
@@ -23,6 +23,7 @@
 int kdump_status[NR_CPUS];
 static atomic_t kdump_cpu_frozen;
 atomic_t kdump_in_progress;
+static int kdump_freeze_monarch;
 static int kdump_on_init = 1;
 static int kdump_on_fatal_mca = 1;
 
@@ -108,10 +109,38 @@ machine_crash_shutdown(struct pt_regs *pt)
         */
        kexec_disable_iosapic();
 #ifdef CONFIG_SMP
+       /*
+        * If kdump_on_init is set and an INIT is asserted here, kdump will
+        * be started again via INIT monarch.
+        */
+       local_irq_disable();
+       ia64_set_psr_mc();      /* mask MCA/INIT */
+       if (atomic_inc_return(&kdump_in_progress) != 1)
+               unw_init_running(kdump_cpu_freeze, NULL);
+
+       /*
+        * Now this cpu is ready for kdump.
+        * Stop all others by IPI or INIT.  They could receive INIT from
+        * outside and might be INIT monarch, but only thing they have to
+        * do is falling into kdump_cpu_freeze().
+        *
+        * If an INIT is asserted here:
+        * - All receivers might be slaves, since some of cpus could already
+        *   be frozen and INIT might be masked on monarch.  In this case,
+        *   all slaves will be frozen soon since kdump_in_progress will let
+        *   them into DIE_INIT_SLAVE_LEAVE.
+        * - One might be a monarch, but INIT rendezvous will fail since
+        *   at least this cpu already have INIT masked so it never join
+        *   to the rendezvous.  In this case, all slaves and monarch will
+        *   be frozen soon with no wait since the INIT rendezvous is skipped
+        *   by kdump_in_progress.
+        */
        kdump_smp_send_stop();
        /* not all cpu response to IPI, send INIT to freeze them */
-       if (kdump_wait_cpu_freeze() && kdump_on_init)   {
+       if (kdump_wait_cpu_freeze()) {
                kdump_smp_send_init();
+               /* wait again, don't go ahead if possible */
+               kdump_wait_cpu_freeze();
        }
 #endif
 }
@@ -140,10 +169,6 @@ kdump_cpu_freeze(struct unw_frame_info *info, void *arg)
        atomic_inc(&kdump_cpu_frozen);
        kdump_status[cpuid] = 1;
        mb();
-#ifdef CONFIG_HOTPLUG_CPU
-       if (cpuid != 0)
-               ia64_jump_to_sal(&sal_boot_rendez_state[cpuid]);
-#endif
        for (;;)
                cpu_relax();
 }
@@ -154,6 +179,20 @@ kdump_init_notifier(struct notifier_block *self, unsigned long val, void *data)
        struct ia64_mca_notify_die *nd;
        struct die_args *args = data;
 
+       if (atomic_read(&kdump_in_progress)) {
+               switch (val) {
+               case DIE_INIT_MONARCH_LEAVE:
+                       if (!kdump_freeze_monarch)
+                               break;
+                       /* fall through */
+               case DIE_INIT_SLAVE_LEAVE:
+               case DIE_INIT_MONARCH_ENTER:
+               case DIE_MCA_RENDZVOUS_LEAVE:
+                       unw_init_running(kdump_cpu_freeze, NULL);
+                       break;
+               }
+       }
+
        if (!kdump_on_init && !kdump_on_fatal_mca)
                return NOTIFY_DONE;
 
@@ -166,43 +205,31 @@ kdump_init_notifier(struct notifier_block *self, unsigned long val, void *data)
        }
 
        if (val != DIE_INIT_MONARCH_LEAVE &&
-           val != DIE_INIT_SLAVE_LEAVE &&
            val != DIE_INIT_MONARCH_PROCESS &&
-           val != DIE_MCA_RENDZVOUS_LEAVE &&
            val != DIE_MCA_MONARCH_LEAVE)
                return NOTIFY_DONE;
 
        nd = (struct ia64_mca_notify_die *)args->err;
-       /* Reason code 1 means machine check rendezvous*/
-       if ((val == DIE_INIT_MONARCH_LEAVE || val == DIE_INIT_SLAVE_LEAVE
-           || val == DIE_INIT_MONARCH_PROCESS) && nd->sos->rv_rc == 1)
-               return NOTIFY_DONE;
 
        switch (val) {
        case DIE_INIT_MONARCH_PROCESS:
-               if (kdump_on_init) {
-                       atomic_set(&kdump_in_progress, 1);
-                       *(nd->monarch_cpu) = -1;
+               /* Reason code 1 means machine check rendezvous*/
+               if (kdump_on_init && (nd->sos->rv_rc != 1)) {
+                       if (atomic_inc_return(&kdump_in_progress) != 1)
+                               kdump_freeze_monarch = 1;
                }
                break;
        case DIE_INIT_MONARCH_LEAVE:
-               if (kdump_on_init)
+               /* Reason code 1 means machine check rendezvous*/
+               if (kdump_on_init && (nd->sos->rv_rc != 1))
                        machine_kdump_on_init();
                break;
-       case DIE_INIT_SLAVE_LEAVE:
-               if (atomic_read(&kdump_in_progress))
-                       unw_init_running(kdump_cpu_freeze, NULL);
-               break;
-       case DIE_MCA_RENDZVOUS_LEAVE:
-               if (atomic_read(&kdump_in_progress))
-                       unw_init_running(kdump_cpu_freeze, NULL);
-               break;
        case DIE_MCA_MONARCH_LEAVE:
                /* *(nd->data) indicate if MCA is recoverable */
                if (kdump_on_fatal_mca && !(*(nd->data))) {
-                       atomic_set(&kdump_in_progress, 1);
-                       *(nd->monarch_cpu) = -1;
-                       machine_kdump_on_init();
+                       if (atomic_inc_return(&kdump_in_progress) == 1)
+                               machine_kdump_on_init();
+                       /* We got fatal MCA while kdump!? No way!! */
                }
                break;
        }
@@ -212,32 +239,29 @@ kdump_init_notifier(struct notifier_block *self, unsigned long val, void *data)
 #ifdef CONFIG_SYSCTL
 static ctl_table kdump_ctl_table[] = {
        {
-               .ctl_name = CTL_UNNUMBERED,
                .procname = "kdump_on_init",
                .data = &kdump_on_init,
                .maxlen = sizeof(int),
                .mode = 0644,
-               .proc_handler = &proc_dointvec,
+               .proc_handler = proc_dointvec,
        },
        {
-               .ctl_name = CTL_UNNUMBERED,
                .procname = "kdump_on_fatal_mca",
                .data = &kdump_on_fatal_mca,
                .maxlen = sizeof(int),
                .mode = 0644,
-               .proc_handler = &proc_dointvec,
+               .proc_handler = proc_dointvec,
        },
-       { .ctl_name = 0 }
+       { }
 };
 
 static ctl_table sys_table[] = {
        {
-         .ctl_name = CTL_KERN,
          .procname = "kernel",
          .mode = 0555,
          .child = kdump_ctl_table,
        },
-       { .ctl_name = 0 }
+       { }
 };
 #endif